China faces a complex and grim trade outlook which is not likely to improve anytime soon, a senior commerce official warned, despite buoyant trade figures in the first quarter.

China's foreign trade retained robust growth in Q1 to reach 6.2 trillion yuan (about 902.47 billion U.S. dollars) in volume, up 21.8 percent year on year.

Vice Commerce Minister Fang Aiqing said at the opening of the 121st China Import and Export Fair, known as the Canton Fair, that factors of uncertainty and instability have notably increased facing China's trade and these difficulties are not short-termed.

Fang, however, said the fundamentals for China's trade development had not changed and the industries between China and developed and developing countries remain complementary.

He said China will continue to push for structural adjustment in trade, carry on innovative reform, coordinate the balanced development of trade and investment, and maintain the stabilizing trend of trade.

The Canton Fair is held every spring and autumn and is seen as a barometer of the country's foreign trade.

The current event will run through to May 5. Nearly 25,000 domestic and foreign companies set up booths.

Xu Bing, spokesperson for the fair, said optimism prevailed as traders were enthusiastic, based on an organizer's pre-event survey and air ticket booking information.

Li Xinghao, president of Chigo Air Conditioning, is one of the upbeat businessman.

He said the company's export of corporate air conditioners grew by 20 percent in Q1 and the trend was expected to continue throughout the year. He attributed the bright prospects to the integration of cloud computing and big data into the manufacturing of air conditioners.